Clinico-pathological aspects of a residual natal tooth: a case report

A Japanese girl was referred to Osaka University Dental Hospital for examination of a tooth-like structure that had erupted following spontaneous exfoliation of a natal tooth in the lower left primary central incisor region. The structure had erupted at 6 months of age, and radiographic and clinical examination showed composition of pulp and dentin, but no enamel. On histological examination, the majority of the dentin area had a tubular dentin-like appearance, while the outer area of the root appeared to be composed of an osteodentin-like substance. Most of the dentin was covered by cementum. These findings suggest that the structure had originated from a developing remnant of the extracted natal tooth, which must have remained in the gingival tissues. We termed this calcified structure a residual natal tooth.     

Electrogastrographic activity in patients who received proximal gastrectomy plus jejunal interposition or total gastrectomy plus jejunal interposition.

Electrogastrograms (EGGs) were recorded in patients both before and after receiving proximal gastrectomy plus jejunal interposition (PGJI) or just after receiving total gastrectomy plus jejunal interposition (TGJI). Intraluminal pressure was also recorded in some postoperative patients. The EGG 3 cpm component (2.5-4.9 cpm) remained after PGJI, but subsequently decreased with a significant reduction in the preoperative to postoperative ratio of the 3 cpm components (P<0.05). The mean frequency of the 3 cpm components increased significantly after PGJI (P<0.05) and its instability factor increased. The EGG 10 cpm components became relatively dominant compared to other frequency components in 2 out of 8 of patients having PGJI but the mean amplitude of 10 cpm decreased. In TGJI patients, only the 10 cpm component was conspicuous in EGG as in the case of total gastrectomy and Roux en Y anastomosis procedures. The spectral frequencies of intraluminal pressure in the interposed jejunum were similar to the EGG of 10 cpm components both in the case of PGJI and TGJI patients. In conclusion, surface EGG could record the electrical activities of the interposed jejunum more easily in patients having had TGJI than in PGJI.     

Antiinflammatory properties of the new antirheumatic agent 4-acetylaminophenylacetic acid

The antiinflammatory activity of 4-acetylaminophenylacetic acid (MS-932) was investigated. MS-932 did not suppress the acute inflammation of carrageenin-induced paw edema in rats or of primary swelling in adjuvant arthritic rats. However, prophylactic treatment with MS-932 inhibited secondary inflammation in adjuvant arthritic rats. MS-932 also restored to normal the weight of the spleen and the serum albumin/globulin ratio of adjuvant arthritic rats. In addition to its prophylactic effect, MS-932 had a therapeutic effect on adjuvant arthritis. In in vitro tests, MS-932 did not inhibit prostaglandin E2 biosynthesis from arachidonic acid by sheep seminal vesicle microsomal enzyme or superoxide generation by guinea pig neutrophils stimulated with opsonized zymosan. MS-932 had no analgesic effect in mice and no antipyretic effect in rats. These results indicate that MS-932 suppresses adjuvant arthritis through modulation of the immune system.     

Surgical technique of experimental lung transplantation in rabbits.

BACKGROUND: Although rabbits have often been used as an experimental model for the analysis of lung preservation, there are no reports of long-term survival after rabbit lung allotransplantation. The purpose of this study was to establish a lung allotransplantation model for the evaluation of acute lung rejection in the rabbit and to investigate the transplantation techniques in the rabbit. METHODS: Left unilateral lung allotransplantations were performed in 10 pairs of Japanese white male rabbits, weighing from 2.8 to 3.7 kg. Rabbits were divided into two groups. Group A rabbits (n=5) received Cyclosporine A (CsA) (20 mg/kg/day) orally for 5 days postoperatively, while Group B rabbits (n=5) received no CsA. All rabbits were sacrificed at the fifth postoperative day for histological examinations. RESULTS: Anastomoses of the pulmonary vein were achieved by using the atrial cuff technique. Satisfied blood flow was obtained in all arterial and venous anastomosis sites. Bronchial anastomosis was also well healed and all rabbits could maintain adequate spontaneous ventilation. In Group A, histopathology revealed that three cases were grade A0, one was grade A1 and the other was A2. In Group B, three cases lived for five days, and histopathology showed two cases were grade A2 and one case was grade A3. CONCLUSION: We established a left unilateral lung allotransplantation model in the rabbit and observed suppression of acute rejection of the transplanted lung by CsA. This study suggests that the rabbit is also an experimental model suited for the analysis of lung preservation as well as lung allotransplant rejection.     

Imaging of a large collection of human embryo using a super-parallel MR microscope.

Using 4 and 8-channel super-parallel magnetic resonance (MR) microscopes with a horizontal bore 2.34T superconducting magnet developed for 3-dimensional MR microscopy of the large Kyoto Collection of Human Embryos, we acquired T(1)-weighted 3D images of 1204 embryos at a spatial resolution of (40 microm)(3) to (150 microm)(3) in about 2 years. Similarity of image contrast between the T(1)-weighted images and stained anatomical sections indicated that T(1)-weighted 3D images could be used for an anatomical 3D image database for human embryology.     

Hippocampal size may contribute to prospective diagnosis of age-related dementia

Background: The hippocampus is a center of cognitive function and therefore hippocampal atrophy is the major factor in cognitive decline. Analysis of hippocampal size may make it possible to predict progression in cognitive impairment. To address this point, the present study investigated the relationship between hippocampal atrophy and dementia using magnetic resonance (MR) images and the Hasegawa Dementia Scale‐Revised (HDS‐R). Methods: The present study was performed on 274 subjects (14–97 years old; average, 66 years; 106 male and 168 female) who had no focal neurological deficit. Hippocampal area and whole brain area were measured in three series of coronal MR images taken from a 5‐mm slice rostrally along dorsal edge of the pons, and hippocampal size normalized by calculating summated hippocampal areas as percentages of summated whole brain areas. Dementia was screened for using HDS‐R. Results: Hippocampal size decreased and HDS‐R reduced with age. Hippocampal atrophy was highly correlated with cognitive deterioration; a critical normalized hippocampal size for HDS‐R of less than 20, which corresponds with mild cognitive impairment and dementia, was found in 65% of over 60‐years old subjects and 98% of subjects with HDS‐R of less than 20 were over 60 years old. Conclusion: There is a high probability that over 60‐year‐old people with a normalized hippocampal size of less than 1.0 would develop dementia in the future, even though their HDS‐R might presently be over 20. Measurement of hippocampal size with coronal MR imaging may therefore contribute to prospective diagnoses of age‐related dementia.     

Pharmacologic preconditioning effects: Prostaglandin E1 induces heat-shock proteins immediately after ischemia/reperfusion of the mouse liver

Prostaglandin E1 (PGE1) has several potential therapeutic effects, including cytoprotection, vasodilation, and inhibition of platelet aggregation. This study investigates the protective action of PGE1 against hepatic ischemia/reperfusion injury in vivo using a complementary DNA microarray. PGE1 or saline was continuously administered intravenously to mice in which the left lobe of the liver was made ischemic for 30 minutes and then reperfused. Livers were harvested 0, 10, and 30 minutes postreperfusion. Messenger RNA was extracted, and the samples were labeled with two different fluorescent dyes and hybridized to the RIKEN set of 18,816 full-length enriched mouse complementary DNA microarrays. Serum alanine aminotransferase and aspartate aminotransferase levels at 180 minutes postreperfusion were significantly lower in the PGE1-treated group than in the saline-treated group. The cDNA microarray analysis revealed that the genes encoding heat-shock protein (HSP) 70, glucose-regulated protein 78, HSP86, and glutathione S-transferase were upregulated at the end of the ischemic period (0 minutes postreperfusion) in the PGE1 group. Our results suggested that PGE1 induces HSPs immediately after ischemia reperfusion. HSPs might therefore play an important role in the protective effects of PGE1 against ischemia/reperfusion injury of the liver.